This invention relates to a dynamic conversion method of input data, a dynamic conversion program of input data, and a dynamic conversion system of input data, capable of processing media data in various formats.
As data communication modes and data retention modes using a computer are diversified and data types go to multimedia, flexibility of data conversion (decode) becomes necessary in a data reception, decode party. For example, if input data is compressed data represented by an extension of “.zip,” the data reception party requires a data conversion module (program) for expanding the compressed file in the “.zip” format. For example, when input data encoded in a specific format is decoded, the data reception party requires a data conversion module for decoding corresponding to the specific format. In this case, in many closed systems, input data can be designed in a fixed data conversion format and thus the reception party may comprise only the specific data conversion module corresponding to the data conversion format. However, in an open system of the Internet, etc., or a system for handling different types of data conversion formats, if the data conversion module is fixed, it is made impossible to handle every input data.
Then, hitherto, the following (A) or (B) system has been adopted:
(A) In the system shown in FIG. 11, input data from an input device is input to an input module 50, output therefrom is input to a data conversion module 51, output therefrom is input to an output module 52, and data is output from the output module 52 to an output device.
Each module is a plug-in module that can be built in later as desired. The input module 50 reads input data from the specified input device and the data conversion module 51 converts input data from the input module 51 into a predetermined data conversion format. The output module 52 outputs the data provided by the data conversion module 51 to the specific output device. Usually, the modules are connected as pipelining and perform data processing concurrently, so that streaming processing of the input data is made possible.
In the described configuration, if an input data file is not a multiplex file, namely, is a file that can undergo only one data conversion (decode) to provide the objective output data, for example, if the data is input data compressed only in a specific format, the data conversion module 51 is one data conversion module for decompressing the input data. If the input data is double encoded as a multiplex file, for example, if the data is compressed and further encrypted, the data conversion module 51 consists of a data conversion module for decrypting the encrypted data and a data conversion module for decompressing the compressed data. The data conversion module 51 is thus built in as a plug-in module as desired in response to the type of data input from an input device, namely, corresponding to the encode level (the number of encode stages) and the encode modes, so that data conversion (decode) can be accomplished for any input data.
(B) FIG. 12 is a block diagram of a system disclosed in JP-A-2000-236386. The destination data format contained in source data before conversion is read by a system conversion controller 60 and streaming conversion modules 61 to 63 required for converting the data into the format are selected and are optimally arranged. The streaming data of the source data is converted (decoded) under the pipeline control of the arranged conversion modules.
The system in (A) involves a problem of lacking flexibility of data processing because the number of pipeline processing stages for performing data processing (plug-in modules) is fixed to the once setup number. That is, once the data conversion module 51 in FIG. 11 is determined, the input data format and the output data format are determined and thus when input data in any other format is input, the data cannot correctly be converted (decoded). The systems in (A) and (B) involve a problem of incapability of handling input data whose output data format is found only at the execution time. The input data whose output data format is found only at the execution time refers to input data in a multiplex file undergoing multiple encoding in different conversion formats not defined before the execution time. The data conversion format at least at the first encode time cannot be known until such input data is actually converted. Therefore, before execution of data conversion, for example, what conversion module 51 in FIG. 11 may be placed cannot be known and, what streaming conversion modules in FIG. 12 may be selected cannot be determined.